JP2006327228A - Self-propelled working machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable both the getting-on from a slope smoothly to an upper target place and a change of the direction in a narrow place and suppressing effectively contacting of a device etc. installed additionally therefor with an obstacle etc. by mistake during running. <P>SOLUTION: Overhanging members 50 and 52 capable of being changed over between the retracted position and an overhung position overhanging downward are installed in front of and behind a lower runner 14. In the overhanging condition, the front overhanging member 50 serves a role to relieve the shock when the lower runner 14 gets on from the slope to the upper situated target place approximately horizontal continued to the top of the slope. The rear overhanging member 52 has a roller 74 to make grounding in the overhung condition, and accomplishes small-diameter turning of the lower runner 14 with rolling of the roller 74. Further the overhanging members 50 and 52 are arranged, when in the retracted position, as retracted inside the contours of crawlers 20L and 20R when viewed from aside. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a self-propelled working machine such as a hydraulic excavator, which has a function capable of moving up and down ramps such as stairs and steep slopes.

  In recent years, self-propelled working machines that can move up and down in a stable state on ramps such as stairs and steep slopes have been developed for the purpose of dismantling buildings. However, when such a work machine climbs up the stairs and climbs onto the upper target site (for example, a flat ground such as a landing), it changes from the previous tilted posture (the posture along the ramp) to the horizontal posture (the target The posture changes after riding on the ground), so that the vehicle body is impacted.

  In view of this, Japanese Patent Application Laid-Open Publication No. 2004-228561 discloses a device in which a front attachment is provided on the front side of the vehicle body in order to suppress an impact when riding on the target location. This front attachment can be switched between an overhanging position that projects further below the lower surface of the crawler for traveling and a storage position that is stored above the lower surface of the crawler and enables traveling by the crawler. Thus, it is attached to the vehicle body frame via a link mechanism.

According to such a work machine, by extending the front attachment at a position before the work machine can climb the stairs, and moving the front attachment to the storage position as the work machine advances from the position. Thus, it is possible to avoid the sudden change of the work machine from the previous inclined posture (post-lifting posture) to the horizontal posture, and to effectively suppress the impact caused by the sudden change.
JP 7-81634 A

  As described above, in a working machine that presupposes ascending / descending on an inclined road, there are cases in which it is desired to change the direction of travel in a limited space such as indoors or narrow alleys. However, since the crawlers for traveling have a considerable length in the front and back, even if you try to turn by these crawlers, there is a limit to the reduction of the turning radius. It is not easy to change.

  Further, in the work machine described in Patent Document 1, since the front attachment is provided at the lower part of the vehicle body frame that cannot be visually recognized from the driver's seat, the operation is performed without recognizing the presence of the front attachment. The front attachment may accidentally contact other obstacles.

  In view of such circumstances, the present invention enables both smooth climbing from the ramp to the upper target place and change of direction in a narrow place, and a device or the like added for that purpose is running. The purpose is to provide a self-propelled working machine that can effectively prevent accidental contact with an obstacle.

  As means for solving the above-mentioned problems, the present invention provides a self-propelled working machine comprising a vehicle body frame provided with crawlers on the left and right sides and capable of ascending and descending a ramp by the operation of the crawler. And an extended position that extends downward from the lower surface of the crawler to support the vehicle body frame in a front-up state, and a storage position that is stored higher than the lower surface of the crawler and allows the crawler to run. A front projecting member attached to the vehicle body frame so as to be switchable to each other and a rear half region of the crawler. The crawler has a rolling element, and the rolling element protrudes below the lower surface of the crawler. The overhanging position that allows the vehicle body frame to turn with the rolling of the rolling element by landing, and is stored above the lower surface of the crawler. A rear projecting member attached to the vehicle body frame so as to be switchable to a retracted position that enables traveling by the crawler, and the projecting position and the retracted position of the front projecting member and the rear projecting member, respectively. Both overhanging members, so that the front overhanging member and the rear overhanging member in the storage position are within the outer shape of the crawler when viewed from the side of the body frame. The shape and position are set.

  According to this configuration, the front projecting member is projected to the upper target ground side at a position before the crawler can climb the ramp, and the front projecting member is gradually moved to the storage position as the work machine advances from this position. By doing so, it is possible to avoid a sudden change of the work machine from the previous tilted posture (post-lifting posture) to the horizontal posture, and to smoothly ride on the upper target site from the ramp. On the other hand, if the rear projecting member is projected to the projecting position and the rolling element is landed, and the other crawler is operated while one of the crawlers is stopped, the one of the rolling elements is accompanied by the rolling of the one of the rolling elements. It is possible to turn the entire self-propelled work machine around the crawler's front end portion as a turning center, thereby changing the direction of the self-propelled work machine in a narrow space.

  In addition, since both of the overhanging members are in the retracted position, the shape and the position are set so as to fit inside the outer shape of the crawler when viewed from the side of the body frame. Even if the operator does not accurately recognize the position, it is possible to effectively suppress inconveniences such as erroneous contact of another obstacle with the overhanging member.

  Here, it is preferable that the rear projecting member is set so that the rolling element is positioned in front of the rear end of the crawler at the projecting position. Thus, by setting the rolling element position at the overhanging position closer to the front side, the turning radius of the small turn when one of the crawlers is operated can be further reduced, and the workability in narrow places can be further improved. be able to.

  The overhang switching means includes a front switching means for moving the front overhang member between the overhang position and a retracted position independently of the rear overhang member, and the rear side independent of the front overhang member. You may make it include the back side switching means which moves an overhang | projection member between the said overhang | projection position and a storage position.

  In this case, if switching control means for controlling the operation of both switching means is provided so that the front switching means and the rear switching means are operated alternatively, while operating the front projecting member Inconvenience of accidentally operating the rear overhanging member during lifting and lowering operations can be avoided, and conversely, inadvertently operating the front overhanging member during a small turn using the rear overhanging member. Can also be avoided.

  As a specific configuration thereof, when using a fluid pressure actuator that operates by receiving supply of working fluid to each of the front switching unit and the rear switching unit, the switching control unit includes the front switching unit and the rear switching unit. Alternatively, a fluid pressure supply source provided in common to the switching means, a position for guiding the working fluid supplied from the fluid pressure supply source only to the front switching means, and a position for guiding only the rear switching means. It is preferable to include a front / rear switching valve that can be switched.

  According to this configuration, it is possible to perform the position switching of the front and rear extension members with a simple configuration using a common fluid pressure supply source, while the front and rear switching valve allows the fluid pressure supply source to supply the fluid pressure. It is possible to selectively switch between a state in which the front switching unit is operated and a state in which the rear switching unit is operated.

  By the way, with respect to the front side overhanging member, it is preferable to set a somewhat large overhanging amount so as to be as close as possible to the upper target position at the overhanging position, whereas the rear overhanging member has at least its rolling elements at the lower surface of the traveling body. Since it is sufficient if there is an overhang that can be landed on the lower side, the overhang position of the front overhang member is more preferably set to a position below the overhang position of the rear overhang member. Therefore, when the front side switching means and the rear side switching means are constituted by a front fluid pressure cylinder and a rear fluid pressure cylinder, respectively, the expansion / contraction stroke of the rear fluid pressure cylinder is made larger than the expansion / contraction stroke of the front fluid pressure cylinder. In such a stroke setting, one end of each of the fluid pressure cylinders is connected to the front projecting member and the rear projecting member, and the other ends of the fluid pressure cylinders are both front and rear of the crawler. By arranging to be connected to the vehicle body frame at a position behind the intermediate direction position, it is possible to secure the stroke required for the front and rear hydraulic cylinders while keeping the whole compact. .

  Further, the overhang switching means does not individually operate the front and rear overhang members as described above, but the front overhang member and the rear overhang member are arranged so that the front overhang member is in the overhang position and the rear A front overhanging state in which the side overhanging member is in a position above the retracted position, a retracted state in which the front overhanging member and the rear overhanging member are both in the retracted position, and the front overhanging member in the upper position of the storage position. An interlocking mechanism for interlocking the two overhanging members so that the rear side overhanging member is switched to the rear side overhanging state in the extended position, and the front side overhanging state by interlocking the two overhanging members with this interlocking mechanism. And interlocking operation means for selectively switching between the neutral state and the rear side overhanging state.

  According to this configuration, the front and rear projecting members can be selectively switched to the projecting position using the common operating means (that is, the front projecting state and the rear projecting state). In addition, when the both projecting members are in the retracted state at the retracted position, normal traveling can be performed without any problem.

  As a specific structure, for example, the front projecting member rotates about a left and right support shaft provided in a front portion of the vehicle body frame, and is switched between the projecting position and the storage position by the rotation. The rear projecting member is rotated about a left and right support shaft provided at the rear portion of the vehicle body frame, and the projecting position and the retracted position are An intermediate link attached to the body frame so as to be rotatable about a left and right support shaft located between the two support shafts. A front link for connecting the front end portion of the intermediate link and the front projecting member, and a rear link for connecting the rear end portion of the intermediate link and the rear projecting member. Operating means, the front overhang member, the rear overhang member, those for rotating one of said intermediate link, is suitable.

  According to this configuration, the intermediate link is simply connected to the front and rear extension members via the front link and the rear link, respectively, and the front extension state and the rear extension state are obtained by interlocking both extension members. And the storage state can be switched alternatively.

  Further, in this structure, a fluid pressure cylinder can be applied as the interlocking operation means. One end of the fluid pressure cylinder is connected to either the front projecting member or the rear projecting member, and the other end is connected to the vehicle body frame. By connecting to the front and rear, the front and rear extension members can be operated in conjunction using the expansion and contraction of the fluid pressure cylinder.

  As described above, according to the present invention, it is possible to achieve a smooth ride from the ramp to the upper target site using the front projecting member, and use the rolling of the rolling elements provided on the rear projecting member. The effect is that the direction of the self-propelled work machine can be changed in a narrow space.

  In addition, since both of the overhanging members are in the retracted position, the shape and the position are set so as to fit inside the outer shape of the crawler when viewed from the side of the body frame. Even if the operator does not accurately recognize the position, it is possible to effectively suppress inconveniences such as erroneous contact of another obstacle with the overhanging member.

  A first embodiment of the present invention will be described with reference to FIGS. Note that the self-propelled working machine 10 shown in this embodiment is one equipped with a scraper (scraping plate member) 12 as a work attachment, but the present invention is not limited to this, and a hydraulic excavator or crusher It can be applied to various self-propelled working machines such as machines.

  A self-propelled working machine 10 shown in FIGS. 1 to 7 includes a lower traveling body 14 and an upper working body 16.

  The lower traveling body 14 includes a vehicle body frame 18 shown in FIGS. 4 and 5 and traveling crawlers 20L and 20R provided on the left and right sides thereof. These crawlers 20L and 20R have iron rings (not shown) arranged in the front and rear, and crawler belts stretched between these iron rings, and have a substantially oval shape extending in the front-rear direction when viewed from the side. .

  A front end of a undulation frame 24 is rotatably connected to the body frame 18 around a horizontal support shaft 22 provided at a front end in the traveling direction, and the upper portion shown in FIGS. A work body 16 is mounted.

  As shown in FIGS. 4 and 5, an upper working body operating cylinder 26 made of a hydraulic cylinder is provided between the hoisting frame 24 and the vehicle body frame 18. One end of the upper work body operating cylinder 26 is pivotally supported on the front end of the body frame 18 via a pin 25 in the left-right direction, and the other end is substantially in the front-rear direction of the hoisting frame 24. The upper and lower frames 24 are undulated by the expansion and contraction of the upper work body operation cylinder 26 and are mounted on the undulation frame 24. The work body 16 is switched between a normal position as shown in FIG. 3 and an inclined position as shown in FIGS. 1 and 2.

  Here, the normal position is a position where the upper working body 16 is supported in a substantially horizontal posture with respect to the lower traveling body 14, and normal traveling is possible at this position. On the other hand, the inclined position is a position where the upper working body 16 is inclined forward and downward by a predetermined angle θ with respect to the lower traveling body 14, and the predetermined angle θ is an elevation of the self-propelled working machine 10. Is set to an angle (about 45 ° in the example) substantially equal to the inclination angle of the ramp (step 28 in the example).

  1 to 3, FIG. 1 shows a state where the self-propelled working machine 10 is moving up and down on the stairs 28, and FIG. 2 shows the self-propelled working machine 10 as described in detail later. FIG. 3 shows a state immediately before riding on the upper target site (the landing 29 in the example of the figure) following the upper end of the staircase 28, and FIG. 3 shows a state after the self-propelled working machine 10 has completely climbed on the landing 29. Show.

  Here, the “upper destination” according to the present invention is not limited to the landing 29, and may be a wide flat surface that continues to the upper end of a steep slope, for example.

  In the present invention, the upper work body 16 does not necessarily have to be switchable between the normal position and the inclined position. For example, when the center of gravity of the entire self-propelled work machine 10 is low, the inclination of the ramp is relatively low. The present invention can also be applied effectively when the ramp can be raised and lowered while the upper working body 16 is kept in the normal position, as in the case of a small size.

  The undulating frame 24 has a slewing bearing portion 30 as shown in FIGS. 4 and 5 at a substantially middle portion in the front-rear direction, and the upper work shown in FIGS. 1 to 3 on the slewing bearing portion 30. The body 16 is supported so as to be able to turn around a vertical axis.

  The upper working body 16 includes a turning body 34 on which a driver's seat 32 is mounted, and a boom support member 36 is provided at the front end of the turning body 34 so as to be rotatable (swing) around a vertical axis 35. It has been. A boom 38 is attached to the boom support member 36 so as to be rotatable (can be raised and lowered) about a left-right axis 37, and can be rotated about a left-right axis 39 at the tip of the boom 38. An arm 40 is attached so that the scraper 12 is provided at the tip of the arm 40 so as to be rotatable about a left-right axis.

  The boom 38 is raised and lowered, the arm 40 is rotated with respect to the boom 38, and the scraper 12 is rotated with respect to the arm 40. The boom cylinder 42, the arm cylinder 44, and the attachment cylinder 46 are hydraulic cylinders, respectively. Realized by expansion and contraction.

  As a feature of the self-propelled working machine 10, a front projecting member 50 and a rear projecting member 52 as shown in FIGS. 4 to 6 are attached to the front and rear portions of the body frame 18, respectively. These overhang members 50 and 52 can be switched between a storage position indicated by a solid line in FIG. 4 and an overhang position indicated by a two-dot chain line in FIG.

  Among these, the front projecting member 50 assists the self-propelled working machine 10 to silently run from the stairs 28 to the landing 29 by the projecting. On the other hand, the rear projecting member 52 is for realizing that the lower traveling body 14 makes a small turn around the front end of the left crawler 20L or the front end of the right crawler 20R.

  The front projecting member 50 includes a rotating arm 53 and a pair of left and right casters 54 that are rolling elements attached to the end of the rotating arm 53.

  The pivot arm 53 includes a pair of left and right pivot side plates 56 and a caster support plate 58. Both the rotating side plates 56 are rotatably attached to the front half portion of the vehicle body frame 18, and the caster support plate 58 is provided so as to connect these rotating side plates 56 to each other. Specifically, the pivot base end portions of both the pivot side plates 56 are pivoted on the pivot shaft 60 so as to be pivotable about a pivot shaft 60 provided in the front half of the body frame 18 in the left-right direction. The pivot tip portions are supported by the caster support plate 58 extending in the left-right direction.

  Each of the casters 54 is attached to the lower side of the caster support plate 58 via a caster bracket 62. These caster brackets 62 are attached to the caster support plate 58 so as to be rotatable about an unillustrated axis extending in the thickness direction of the caster support plate 58, and the caster 54 is attached to the caster support plate 58. It is rotatably held via an axis 64 in a direction parallel to the axis.

  A front projecting member operating cylinder 66 made of a hydraulic cylinder is interposed between the rotating side plate 56 and the vehicle body frame 18, and the front projecting member 50 is brought into the retracted position by expansion and contraction of the front projecting member operating cylinder 66. Rotation operation is performed between the overhang positions.

  Specifically, a cylinder bracket 68 that protrudes downward from the lower surface of the vehicle body frame 18 is provided at a portion of the vehicle body frame 18 that is behind the intermediate position in the front-rear direction, and the cylinder bracket 68 is provided with a front extension member operation cylinder 66. The head-side end portion is connected to the left and right pins 70 so as to be relatively rotatable, and the rod-side end portion of the front projecting member operating cylinder 66 is turned to the both directions via the left and right pins 72. The side plate 56 is connected to the vicinity of the rotation base end portion so as to be relatively rotatable.

  Then, in a state where the front projecting member operating cylinder 66 is extended, the entire front projecting member 50 is stored in a storage position that fits inside the outer shape of the crawlers 20L and 20R as seen from the side as shown by a solid line in FIG. When the front projecting member operating cylinder 66 contracts, the front projecting member 50 is projected to a projecting position that largely protrudes from the lower surfaces of the crawlers 20L and 20R, as indicated by a two-dot chain line in FIG. . As shown in FIG. 2, the amount of overhang is such that the caster 54 of the front overhang member 50 in the overhang position lands on the landing 29 just before the self-propelled working machine 10 reaches the landing 29. The overhang amount is set at or near the overhang amount.

  On the other hand, the rear projecting member 52 includes a rotating arm 73 and a pair of left and right casters 74 which are rolling elements attached to the end of the rotating arm 73, as with the front projecting member 50.

  The pivot arm 73 includes a pair of left and right pivot side plates 76 and a caster support plate 78. Both the rotation side plates 76 are rotatably attached to the rear end portion of the vehicle body frame 18, and the caster support plate 78 is provided so as to connect the rotation side plates 76 to each other. Specifically, a bracket 79 projects rearward from the rear end of the vehicle body frame 18, and the rotation base end portions of the both rotation side plates 76 can rotate about the support shaft 80 in the left-right direction. The pivot tips of the pivot side plates 76 are pivotally supported so as to be connected to each other by the caster support plates 78 extending in the left-right direction.

  Each caster 74 is attached to the lower side of the caster support plate 78 through a caster bracket 82 in the same manner as the caster 54. That is, the left and right caster brackets 82 are attached to the caster support plate 78 so as to be rotatable about an unillustrated axis extending in the thickness direction of the caster support plate 78, and the caster 74 is supported by the caster. It is rotatably held via an axis 84 in a direction parallel to the plate 78.

  A rear projecting member operating cylinder 86 made of a hydraulic cylinder is also interposed between the rotating side plate 76 and the vehicle body frame 18, and the rear projecting member 52 is moved by the expansion and contraction of the rear projecting member operating cylinder 86. A rotation operation is performed between the storage position and the overhang position.

  Specifically, the head side end portion of the rear extension member operating cylinder 86 is relative to the cylinder bracket 68 via a left and right pin 90 positioned slightly rearward of the pin 70 in the cylinder bracket 68. The rod-side end of the rear-side extending member operating cylinder 86 can be relatively rotated to a portion in the vicinity of the rotation base end portions of the both rotation-side plates 76 via a pin 92 in the left-right direction. It is connected to. Then, in a state where the rear side extension member operating cylinder 86 is extended, the rear side extension member 52 as a whole is stored in a retracted position that fits inside the outer shape of the crawlers 20L and 20R as seen from the side as shown by the solid line in FIG. On the other hand, when the rear side extension member operating cylinder 86 contracts, the rear side extension member 52 is extended to the extension position protruding downward from the lower surfaces of the crawlers 20L and 20R, as shown by the two-dot chain line in FIG. It is like that.

  The projecting position of the rear projecting member 52 is above the projecting position of the front projecting member 50, and the projecting position of the lower traveling body 14 with the rolling of the caster 54 is enabled by the projecting. Is set to That is, in the state in which the rear side extension member 52 is in the extension position, for example, by operating the left crawler 20L in the forward direction while the right crawler 20R is stopped, the front end position of the right crawler 20R is turned to the right. The lower traveling body 14 turns slightly to the right as the center, and conversely, the left crawler 20L is operated in the forward direction while the left crawler 20L is stopped, so that the front end position of the left crawler 20L is the left turning center. The lower traveling body 14 is turned slightly to the left.

  FIG. 7 shows an example in which the entire self-propelled working machine 10 is turned 180 ° at the landing 29 using the small turn as described in detail later. In this example, only the left crawler 20L is shown. By repeating the above-mentioned operation, the small turn is repeated with the front end portion of the right crawler 20R as the turning center O, so that the turning in the narrow landing 29 is possible.

  Further, in this embodiment, in view of the fact that the projecting position of the front projecting member 50 is below the projecting position of the rear projecting member 52 (that is, the projecting amount is large), the operating means of both projecting members 50 and 52 is used. While shifting the position of the cylinder bracket 68 to which the head side ends of the overhang member operating cylinders 66 and 86 are connected to the rear side of the center position in the front-rear direction of the lower traveling body 14, Considerations are made so that the cylinder strokes required for both the front and rear operation cylinders 66 and 86 can be sufficiently secured.

  Further, with respect to the rear extension member 52, by making the shape of the rotating side plate 76 bent downward at the middle portion thereof, while sufficiently securing the cylinder stroke of the rear extension member operation cylinder 86, The entire rear projecting member 52 in the retracted position is designed to be accommodated inside the outer shape of the crawlers 20L and 20R when viewed from the side.

  In this way, the both overhang members 50 and 52 are accommodated inside the outer shape of the crawlers 20L and 20R in the retracted position, so that the operator can accurately grasp the actual position of the overhang members 50 and 52. Even without this, it is possible to effectively suppress the inconvenience that these projecting members 50 and 52 come into contact with other obstacles during traveling.

  As for the rolling surfaces of the casters 54 and 74, the central portion in the width direction is arranged so that the casters 54 and 74 and the caster holding members 62 and 82 can be easily rotated (rotation that changes the direction of the casters 54 and 74). The surface swells outward in the radial direction. Further, mudguard plates 55 and 75 are attached to the outer end portions of the respective rotating arms 53 and 73 in order to protect these casters 54 and 74.

  In addition to the casters 54 and 74, the rolling members provided on the overhang members 50 and 52 may be held on the rotating arms 53 and 73 so as to be freely rotatable. In addition, as for the front projecting member 50, if the landing portion has a shape that allows easy sliding on the landing 29, the rolling elements can be appropriately omitted.

  Next, referring to FIGS. 8 to 10, fluid pressure circuits (hydraulic circuits in the illustrated example) mounted on the self-propelled work machine 10 to operate the hydraulic cylinders and the travel motors and swing motors (not shown) will be described. While explaining.

  The hydraulic circuit includes main pumps 101 and 102 including a hydraulic pump and a pilot pump 104 as a hydraulic pressure supply source. These pumps 101, 102, 104 are connected to the output shaft of the engine 100, and discharge hydraulic fluid when driven.

  Both the main pumps 101 and 102 supply hydraulic oil to each hydraulic actuator mounted on the self-propelled work machine 10. Specifically, in addition to the upper work body operation cylinder 26, the boom cylinder 42, the arm cylinder 44, the attachment cylinder 46, and the both overhang member operation cylinders 66 and 86, the span cylinder that expands and contracts the spans of the left and right crawlers 20L and 20R. 106, although not shown, a left and right traveling motor for operating the left and right crawlers 20L and 20R, a turning motor for turning the upper working body 16, a swing cylinder for turning the boom support member 36 to the left and right, etc. Supply hydraulic oil to

  A control valve block 110 is interposed between the main pumps 101 and 102 and the hydraulic actuators. The control valve block 110 includes a center bypass passage 111 that guides hydraulic oil supplied from the main pump 101 through the supply oil passage 121 to the tank 108, and hydraulic oil supplied from the main pump 102 through the supply oil passage 122. A center bypass passage 112 leading to the tank 108 and a plurality of control valves are arranged in series along the center bypass passages 111 and 112.

  Specifically, on the side of the center bypass passage 111, an arm control valve 113 connected to the arm cylinder 44, a swing control valve 114 connected to the swing motor, and a left travel connected to the left travel motor. The control valve 115 is arranged, and on the center bypass passage 112 side, an attachment control valve 116 connected to the attachment cylinder 46, a boom control valve 117 connected to the boom cylinder 42, and the swing cylinder The swing control valve 118 to be connected, the right travel control valve 119 connected to the right travel motor, the span cylinder 106, the upper work body operation cylinder 26, and the front and rear extension member operation cylinders 66 and 86 are provided in common. A common control valve 120 is arranged.

  These control valves 113 to 120 are each constituted by a three-position direction switching valve having a flow rate adjusting function (the swing control valve 117 is a manual switching valve, and the other control valves are hydraulic pilot switching valves). In the middle position in the figure, the hydraulic oil supplied from the main pump 101 or the main pump 102 is bypassed to the tank 108 side as it is, while the pilot operation or the manual operation by the pilot pressure of the pilot pump 104 is performed from the neutral position. The hydraulic fluid is guided to the connected hydraulic actuator at a flow rate corresponding to the operation amount.

  A travel remote control valve 124 is interposed between the pilot pump 104 and the travel control valves 115 and 118. The travel remote control valve 124 has left and right travel levers 125L and 125R as shown in FIGS. 11 (a) and 11 (b), and a travel control valve corresponding to the travel lever serves as a pilot portion corresponding to the operation direction. A pilot pressure having a magnitude corresponding to the operation amount is introduced. Therefore, by operating the travel levers 125L and 12R of the travel remote control valve 124, the left and right crawlers 20L and 20R can be traveled at a speed corresponding to the operation amount.

  Further, in this embodiment, relief oil passages 126A and 126B branch from the supply oil passages 121 and 122 to the tank 108 side, respectively, and flow relief valves 127A and 127B and switching are provided in the relief oil passages 126A and 126B, respectively. Valves 128A and 128B are arranged in series, respectively.

  Both switching valves 128A and 128B can be switched between a shut-off position (left position in the figure) for blocking the escape oil paths 126A and 126B and a release position (right position in the figure) communicating with the oil paths 126A and 126B. There is a switching operation in conjunction with the blocking position and the escape position. Therefore, when both the switching valves 128A and 128B are switched to the shut-off position, the total amount of oil discharged from the main pumps 101 and 102 is sent to the control valve block 110, so that the normal amount corresponding to the operation amount of the travel lever is reached. While the hydraulic oil supply flow rate and the normal running speed are ensured, when the switching valves 128A and 128B are switched to the escape position, the hydraulic oil supply flow rate is reduced by the relief amount and the travel lever is fully operated. The traveling speed at the time, that is, the maximum speed is limited.

  Next, a hydraulic pressure supply system from the main pump 102 to the cylinders 106, 26, 66, 86 via the common control valve 120 will be described.

  The common control valve 120 has pilot portions 131 and 132, and electromagnetic switching valves 133 and 134 are provided between the pilot portions 131 and 132 and the pilot pump 104, respectively. Each of the electromagnetic switching valves 133 and 134 has solenoids b1 and b2, respectively. In the off state where the solenoids b1 and b2 are not energized, the pilot oil from the pilot pump 104 is released to the tank 108, while the solenoids In the ON state in which b1 and b2 are energized, the pilot oil is guided to the pilot parts 131 and 132 to generate a pilot pressure.

  The common control valve 120 maintains a neutral position (center bypass position) when pilot pressure is not supplied to both pilot parts 131 and 132 or when equivalent pilot pressure is supplied, while pilot pressure is applied only to the pilot part 131. Is supplied to the oil passage 137 and switched to a position (lower position in the figure) where the oil passage 138 is connected to the tank 108 side. When pilot pressure is supplied only to the pilot section 132, the pump discharge oil is discharged. The oil is guided to the oil passage 138 and switched to the position (the upper position in the figure) where the oil passage 137 is connected to the tank 108 side.

  The oil passage 137 branches into two branch oil passages 141 and 142, and the oil passage 138 branches into two branch oil passages 144 and 145. On the downstream side thereof, an electromagnetic switching valve 148 for switching the span cylinder 106 or the upper work body operating cylinder 26 between an operating state and a stopped state, and the front side extending member operating cylinder 66 or the rear side extending member operating cylinder 86 are provided. An electromagnetic switching valve 147 for switching between an operating state and a stopped state, a selection valve 150 for switching the span cylinder 106 and the upper work body operating cylinder 26 alternatively to an operable state by manual operation, and manual operation Are provided with front and rear switching valves 152 and 154 for selectively switching the front and rear projecting member operating cylinders 66 and 86 to an operable state.

  Specifically, among the branch oil passages 141, 142, 144, 145, the branch oil passage 141 reaches the front / rear switching valve 152 through an electromagnetic switching valve 147, and the front / rear switching valve 152 is operated by the manual operation. A front selection position (lower position in the figure) for connecting the branch oil passage 141 to the head side chamber of the front extension member operation cylinder 66 and a rear selection position for connecting to the head side chamber of the rear extension member operation cylinder 86 ( (The upper position in the figure). Further, the branch oil passage 142 reaches the selection valve 150 through an electromagnetic switching valve 148, and the selection valve 150 manually selects the span to connect the branch oil passage 142 to the rod side chamber of the span cylinder 106. The position is selectively switched between the position (left position in the figure) and the upper work body operation selection position (right position in the figure) connected to the rod side chamber of each upper work body operation cylinder 26.

  On the other hand, the branch oil passage 144 reaches the front / rear switching valve 154 through the electromagnetic switching valve 147. The front / rear switching valve 154 is manually operated so that the branch oil passage 144 is connected to the rod side chamber of the front extension member operation cylinder 66 at the front selection position (lower position in the figure) and the rear extension member operation cylinder 86. It is alternatively switched to a rear selection position (upper position in the figure) connected to the rod side chamber. Further, the branch oil passage 145 reaches the head side chamber of each upper work body operating cylinder 26 and the head side chamber of the span cylinder 106 through the electromagnetic switching valve 148.

  The electromagnetic switching valve 147 has a solenoid a1, and when the solenoid a1 is not energized, the electromagnetic switching valve 147 is switched to a valve closing position (right side position in the figure) that shuts off both the branch oil passages 141 and 144. In the ON state in which the solenoid a1 is energized, the valve is switched to the valve opening position (left position in the figure) where both the branch oil passages 141 and 144 are opened. Similarly, the electromagnetic switching valve 148 has a solenoid a2, and when the solenoid a2 is not energized, the electromagnetic switching valve 148 is switched to a valve closing position (right position in the figure) that shuts off both the branch oil passages 142 and 145. On the other hand, in the ON state in which the solenoid a2 is energized, the valve is switched to the valve opening position (left position in the figure) where both the branch oil passages 142 and 145 are opened.

  A controller (valve control means) 156 comprising a microcomputer or the like is attached to the hydraulic circuit, and the solenoids b1 and b2 of the electromagnetic switching valves 133 and 134 and the electromagnetic switching valve 147, in accordance with a control signal output from the controller 156. 148 solenoids a1 and a2 are switched on and off.

  The travel remote control valve 124 is incorporated in an operation box 160 as shown in FIGS. 11 (a) and 11 (b), and is detachably attached to the vicinity of the driver's seat 32 together with the operation box 160. The operation box 160 is connected to the controller 156 through a wiring not shown. When the stairs 28 is raised or lowered, the traveling remote control valve 124 and the operation box 160 are removed from the upper work body 16 and the traveling remote control valve 124 and the operation box 160 are self-propelled through the hydraulic hose and the wiring not shown. The machine 10 can be remotely operated.

  The controller 156 may be provided on the operation box 160 side.

  The operation box 160 has a space 162 in the center where the travel remote control valve 124 can be stored, and a draw (upper work body undulation) / span operation switch 163, caster operation (extension) A member operation) switch 164, a tuning switch 166, and an emergency stop button 168 are provided.

  The draw / span operation switch 163 is operated from the normally held neutral position to the upper side or the lower side thereof, thereby raising or lowering the upper work body 16 (that is, raising / lowering between the inclined position and the normal position). Alternatively, an instruction to enlarge / reduce the width between the crawlers 20L and 20R is output to the controller 156.

  The caster operation switch 164 is operated from the normally held neutral position to the upper side or the lower side to raise or lower the front extension member 50 or the rear extension member 52 (that is, between the retracted position and the extension position). Rotation) command is output to the controller 156.

  The tuning switch 166 outputs a command to switch the control mode of the controller 156 between the tuning control mode and the independent control mode by the on / off operation. Here, the tuning control mode is a mode for executing the following tuning control.

  a) When the stairs rise, as shown in FIG. 2, the position immediately before reaching the landing 29 immediately before the self-propelled working machine 10 reaches the landing 29 that is located at the upper end of the stairs 28 (the front ends of both the crawlers 20L and 20R are the regions of the stairs 28 The front projecting member 50 is projected to the projecting position and the caster 54 is projected to the projecting field 29 at a position where both the crawlers 20L and 20R are not on the landing 29). When the front projecting member 50 is retracted to its retracted position from the grounded state, the upper working body operation cylinder 26 contracts to reduce the upper working body operation cylinder 26 so that the upper working body 16 maintains a substantially horizontal state. The upper working body 16 is returned from the inclined position to the normal position, and the front side extension member operating cylinder 66 is extended from the extension position to the front. Tuning the store to the storage position.

  b) On the contrary, when the self-propelled working machine 10 is moved backward to the position where the rear ends of the crawlers 20L and 20R protrude from the landing 29 to the stairway 28 side when the stairs descend, When the two crawlers 20L and 20R of the self-propelled work machine 10 are tilted to the angle at which the crawlers 20L and 20R ride on the stairs 28 by being extended from the retracted position to the extended position, In order to maintain a substantially horizontal state, the front side extension member 50 is extended from the retracted position to the extended position by contraction of the front side extension member operation cylinder 66, and the upper work body operation cylinder 66 is inclined from the normal position. The tilting operation of the upper working body 16 to the position is synchronized.

  The emergency stop button 168 is pressed to stop the movement of each actuator in an emergency when an accident occurs during the work.

  Based on such a command operation performed in the operation box 160, the controller 156 performs on / off control of the solenoids a1 and a2 of the electromagnetic switching valves 147 and 148 and the solenoids b1 and b2 of the electromagnetic switching valves 133 and 134. The contents are as follows.

  First, for the solenoids a1 and a2, when the tuning switch 166 is on, both the solenoids a1 and a2 are turned on. When the tuning switch 166 is off, the solenoid a2 is turned on when the draw / span operation switch 163 is operated, and the solenoid a1 is turned on when the caster operation switch 164 is operated. Otherwise, solenoids a1 and a2 are kept off.

  On the other hand, for the solenoids b1 and b2, when the draw / span operation switch 163 is operated to the “down” side or the caster operation switch 164 is operated to the “up” side, the solenoid b1 is turned on, and conversely, the draw When the / span operation switch 163 is operated to the “down” side or the caster operation switch 164 is operated to the “up” side, the solenoid b2 is turned on. Otherwise, solenoids b1 and b2 are kept off.

  Next, an operation procedure for raising the self-propelled working machine 10 along the stairs 28 and an operation associated with the operation will be described.

A. Preparation for climbing First, before ascending the stairs 28 to the self-propelled work machine 10, the following preparation work is performed.

  1) Minimize the width (span) between the crawlers 20L and 20R. In order to perform this operation, the selection valve 150 in the hydraulic circuit shown in FIG. 8 is manually switched to the left span selection position and the tuning switch 166 of the operation box 160 is turned off, / Span operation switch 163 may be operated to the “down” side. Upon receiving the command signal output by the switch operation, the controller 156 opens the electromagnetic switching valve 148 by turning on only the solenoid a2 of the solenoids a1 and a2 of the electromagnetic switching valves 147 and 148. Of the solenoids b1 and b2 of 133 and 134, only the solenoid b1 is switched on. As a result, the common control valve 120 is switched from the neutral position to the lower position in FIG. 8, and hydraulic oil discharged from the main pump 102 flows from the center bypass passage 112 to the common control valve 120, the electromagnetic switching valve 148, and the The gas is introduced into the rod side chamber of the span cylinder 106 through the selection valve 150 in order. With this hydraulic pressure supply, the span cylinder 106 contracts, and the width between the crawlers 20L and 20R is reduced.

  2) After fully pulling the arm 40 and raising the boom 38 fully, the arm 40 and the boom 38 are fully swung leftward together with the boom support member 36. By this operation, the forward protrusion amount of the boom 38 and the arm 40 is minimized. However, in FIG. 1 to FIG. 3, for convenience, the state where the swing is not performed is illustrated.

  3) Both the front and rear projecting members 50 and 52 are pulled up to the retracted position. The front projecting member 50 is stored in a state in which both the front and rear switching valves 152 and 154 are manually set to the front side selected position (the lower position in FIG. 9) with the tuning switch 160 turned off (ie, switched to the independent control mode). ) And then the caster operation switch 164 may be operated to the “up” side. Thus, the controller 156 that receives the command signal output from the switch 164 switches on only the solenoids a1 and b1 of the solenoids a1, a2, b1, and b2. As a result, the common control valve 120 is switched from the neutral position to the lower position in FIG. 9, and the electromagnetic switching valve 147 is switched to the valve opening position, and is discharged from the main pump 102 as shown by the bold line in FIG. The hydraulic oil is introduced from the center bypass passage 112 into the head side chamber of the front extension member operation cylinder 66 through the common control valve 120, the electromagnetic switching valve 147, and the front / rear switching valve 152 in order. By the supply of the hydraulic pressure, the front projecting member operating cylinder 66 extends, and the front projecting member 50 is switched to the storage position indicated by the solid line in FIG.

  Further, if the front / rear switching valves 152, 154 are switched to the rear selected position in the upper stage of the figure from this state, the hydraulic oil is supplied to the head side chamber of the rear extension operating cylinder 86. As the cylinder 86 extends, the rear projecting member 52 is also switched to the storage position shown by the solid line in FIG.

  In the illustrated example, the storage positions of these overhanging members 50 and 52 are all within the outer shape of the crawlers 20L and 20R when viewed from the side, and the crawlers 20L and 20R can be run while being run. It is difficult to touch other obstacles.

  In addition, after this storing operation is completed, the front / rear switching valves 152 and 154 are switched to the front switching position in advance.

  4) The traveling remote control valve 124 is removed from the driver's seat 32 together with the operation box 160 and moved to a predetermined remote operation position.

  5) The switching valves 128A and 128B are switched to the escape position (right side position in FIGS. 8 to 10), and both relief oil passages 126A and 126B are opened.

B. Stair Climbing After the preparation work is completed, the stairs 28 are climbed in the following procedure.

  1) Orient the self-propelled work machine 10 in a direction perpendicular to the stairs 28.

  2) Operate both travel levers 125L, 125R in the forward direction. By this operation, the pilot pressure from the pilot pump 104 is supplied to the forward pilot portions of the left travel control valve 115 and the right travel control valve 118 so that both control valves 115 and 118 are in the forward position side (upper position side in the figure). The oil discharged from the main pumps 101 and 102 is supplied to the left and right traveling motors through the traveling control valves 115 and 118. At this time, if the switching valves 128A and 128B are open, a part of the oil discharged from the main pumps 101 and 102 is released to the tank 108 from the relief oil passages 126A and 126B. Even when the levers 125L and 125R are fully operated, the speed (maximum speed) at that time reaches a low speed suitable for ascending and descending stairs. Therefore, it is possible to slowly climb the stairs 28 while fully operating both the travel levers 125L and 125R, thereby reducing the burden on the operator and ensuring high safety.

  3) When the crawlers 20L and 20R ride on the first staircase 28 in the above-described manner, the entire self-propelled work machine 10 starts to tilt upward. From this point, the upper work body 16 is slightly moved with respect to the lower travel body 14. The upper work body 16 is kept substantially horizontal regardless of the inclination of the lower traveling body 14 by inclining forwardly downward (so-called draw operation). In order to perform such a drawing operation, the selection valve 150 in the hydraulic circuit shown in FIG. 8 is manually switched to the drawing selection position on the right side of the drawing, and in that state, the tuning switch 166 of the operation box 160 is turned on. The draw / span operation switch 163 may be operated to the “up” side with the switch off.

  The controller 156 that receives the command signal output by this switch operation turns on only the solenoid a2 of the solenoids a1 and a2 of the electromagnetic switching valves 147 and 148 to switch the electromagnetic switching valve 148 to the valve open position, and Of the solenoids b1 and b2 of the switching valves 133 and 134, only the solenoid b2 is switched on. As a result, the common control valve 120 is switched from the neutral position to the upper position in FIG. 8, and the hydraulic oil discharged from the main pump 102 flows from the center bypass flow path 112 to the common control valve 112 as indicated by a thick broken line in FIG. 120, the electromagnetic switching valve 148, and the selection valve 150 are sequentially introduced into the head side chamber of the upper work body operating cylinder 26. By supplying the hydraulic pressure, the upper working body operating cylinder 26 extends to lift the rear part of the upper working body 16, and the upper working body 16 is inclined forward and downward with respect to the lower traveling body 14.

  When the parallel operation of the draw operation and the forward operation of the lower traveling body 14 is completed and the entire crawlers 20L and 20R completely ride on the staircase 28, as shown in FIG. The upper working body 16 reaches an inclined position where it is inclined with respect to the lower traveling body 14 by an equivalent angle θ. In this state, the stairs 28 can be climbed while maintaining the upper working body 16 substantially horizontally.

C. Riding on the landing place The position immediately before the climbing and the landing on the landing place 29 (that is, as shown in FIG. When the position reaches the position where the center of gravity has not moved to the side), the crawlers 20L and 20R are temporarily stopped to stop the self-propelled work machine 10 and are then taken on the landing 29 in the following procedure.

  1) The front projecting member 50 is lowered from the retracted position to the projecting position, and the caster 54 is landed on the landing 29 as shown in FIG. In order to perform such an overhanging operation, the tuning switch 166 of the operation box 160 is turned off while the front and rear switching valves 152 and 154 are manually switched to the front switching position (lower position in FIG. 9) in advance. The caster operation switch 163 may be operated to the “down” side as it is.

  The controller 156 that has received a command signal output by this switch operation turns on only the solenoid a1 of the solenoids a1 and a2 of the electromagnetic switching valves 147 and 148 to switch the electromagnetic switching valve 147 to the valve open position. Of the solenoids b1 and b2 of the switching valves 133 and 134, only the solenoid b2 is switched on. As a result, the common control valve 120 is switched from the neutral position to the upper position in FIG. 9, and the hydraulic oil discharged from the main pump 102 flows from the center bypass passage 112 to the common control valve 112 as indicated by the thick broken line in FIG. 9. 120 and the electromagnetic switching valve 147 are sequentially introduced into the rod side chamber of the front extending member operating cylinder 66. By this hydraulic pressure supply, the front overhang member operating cylinder 66 contracts, and the front overhang member 50 is pulled down from the retracted position shown by the solid line in FIG. 4 to the overhang position shown by the two-dot chain line in FIG.

  It should be noted that this overhanging position does not necessarily have to be a position that projects downward until the caster 54 has landed, as long as the caster 54 approaches the upper surface of the landing 29 to some extent. If the caster 54 does not land at this time, it will land at the next slow advance.

  At this time, the front / rear switching valves 152 and 154 are in a state where the main pump 102 and the rear extension member operation cylinder 86 are disconnected from each other and no hydraulic oil is supplied to the cylinder 86. There is no possibility that the rear side overhanging member 52 is accidentally overhanged during overhanging.

  2) From the state shown in FIG. 2, the traveling levers 125L and 125R are operated little by little to gradually advance the lower traveling body 14, while the tuning switch 166 of the operation box 160 is switched on (that is, the tuning control mode is set). Then, the span / draw operation switch 163 is operated to the “down” side or the caster operation switch 164 is operated to the “up” side (automatic tuning operation).

  The controller 156 that receives the command signal by this operation turns on both the solenoids a1 and a2 of the electromagnetic switching valves 147 and 148 to switch both the switching valves 147 and 148 to the open position, and the electromagnetic switching valves 133 and 134 Of the solenoids b1 and b2, only the solenoid b1 is turned on. As a result, the common control valve 120 is switched from the neutral position to the lower position in FIG. 10, and the hydraulic oil discharged from the main pump 102 flows from the center bypass passage 112 to the common control valve 112 as shown by the bold line in FIG. 120, the electromagnetic switching valve 147, and the front / rear switching valve 152 are sequentially introduced into the rod side chamber of the front extension member operation cylinder 66, and at the same time, the common control valve 120 to the electromagnetic switching valve 148 and the selection valve. 150 is supplied to the rod side chamber of the upper work body operating cylinder 26 via 150.

  By such simultaneous hydraulic pressure supply to the upper work body operation cylinder 26 and the overhang member operation cylinder 66, the upper work from the inclined position (FIG. 2) to the normal position (FIG. 3) due to the contraction of the upper work body operation cylinder 26. The return operation of the body 16 and the storage operation from the extension position of the front extension member 50 by the extension of the front extension member operation cylinder 66 to the storage position are performed in synchronization. By slowly moving the body 14 forward, the upper working body 16 is maintained in a substantially horizontal state, while the lower traveling body 14 is quietly (that is, the upper ends of the crawlers 20L and 20R suddenly land on the landing 29). As shown in FIG. 3, it is possible to completely get on the landing 29.

  At this time, if the tuning switch 166 is switched on as described above, the operator can perform the tuning operation only by either lowering the draw / span operation switch 163 or raising the caster operation switch 164. However, if it is desired to perform the tuning operation manually according to the operator's preference, the drawing can be performed with the tuning switch 166 turned off. The lowering operation of the / span operation switch 163 and the raising operation of the caster operation switch 164 may be appropriately performed in parallel.

  In this case, the solenoid b1 of the electromagnetic switching valve 133 and the solenoid a1 of the electromagnetic switching valve 147 are switched on only during a period in which the operator raises the caster operation switch 164, the front extension member operation cylinder 66 extends, The solenoid b1 of the electromagnetic switching valve 133 and the solenoid a2 of the electromagnetic switching valve 148 are switched on only during the period during which the draw / span operation switch 163 is lowered, and the upper work body operating cylinder 26 contracts. Further, when the lowering operation of the draw / span operation switch 163 and the raising operation of the caster operation 164 are simultaneously performed, the solenoids a1, a2 and b1 are simultaneously turned on, and the extension of the front extension member operation cylinder 66 is increased. The upper work body operation cylinder 26 is contracted simultaneously.

  In contrast to this work, when going down from the landing 29 to the stairs 28, basically the reverse operation may be performed. That is, the following operations may be performed in order.

  1 ') The lower traveling body 14 is moved backward from the landing 29 to the stairs 28 side.

  2 ') The lower traveling body is located at a position where the crawlers 20L, 20R of the lower traveling body 14 protrude from the landing 29 toward the stairway 28 and before the center of gravity of the self-propelled work machine 10 moves toward the staircase 28. Stop 14 backwards.

  3 ′) While slowly moving the lower traveling body 14 backward, the tuning switch 166 is turned on and the draw / span operation switch 163 is operated to the “up” side, or the caster operation switch 164 is set to the “down” side. To operate. As a result, the solenoid a1 of the electromagnetic switching valve 147, the solenoid a2 of the electromagnetic switching valve 148, and the solenoid b2 of the electromagnetic switching valve 134 are simultaneously turned on, and the upper work body 16 is tilted by the extension of the upper work body operation cylinder 26. And the extension operation of the front extension member 50 by the contraction of the front extension operation cylinder 66 is performed simultaneously. Thereby, the self-propelled working machine 10 is quietly moved from the position on the landing 29 shown in FIG. 3 to the position inclined along the stairs 28 as shown in FIG. 2 while maintaining the upper working body 16 in a substantially horizontal state. Will be transferred to.

  4 ') The tuning switch 166 is turned off, and the caster operation switch 164 is operated to the "up" side to store the front projecting member 50 in the storage position. By moving the lower traveling body 14 backward in this state, the stairs 28 can be lowered.

D. Turn at the landing After the lower traveling body 14 has completely landed on the landing 29 in the above operation, the normal traveling of the self-propelled working machine 10 is possible, but when the direction of the self-propelled working machine 10 is to be largely changed in a narrow place. For example, when it is desired to turn the self-propelled working machine 10 180 ° within a very limited landing space 29 as shown in FIG. 7, the rear projecting member 52 is lowered from the retracted position to the projecting position. To do. In this operation, the caster operation switch 163 is turned off with the tuning switch 166 of the operation box 160 turned off while the front and rear switching valves 152 and 154 are manually switched to the rear switching position (upper position in FIG. 9) in advance. Can be operated to the “down” side.

  The controller 156 that has received the command signal output by the switch operation switches on only the solenoid a1 of the solenoids a1 and a2 of the electromagnetic switching valves 147 and 148 and also switches the solenoids b1 and b2 of the electromagnetic switching valves 133 and 134. Only the solenoid b2 is switched on. As a result, the common control valve 120 is switched from the neutral position to the lower position in FIG. 9, and hydraulic oil discharged from the main pump 102 flows from the center bypass passage 112 to the common control valve 120, the electromagnetic switching valve 147, and the front and rear It is introduced into the rod side chamber of the rear extension member operating cylinder 86 via the switching valve 154 in order. The supply of the hydraulic pressure causes the rear side extension member operation cylinder 86 to contract, and the rear side extension member 52 is pulled down from the retracted position indicated by the solid line in FIG. 4 to the extended position indicated by the two-dot chain line in FIG.

  Thus, the rear projecting member 52 projects downward, so that the caster 74 is landed on the landing 29, and the rear portion of the lower traveling body 14 is lifted by the projecting portion and tilted forward. Become. In this state, for example, when the right traveling lever 125R remains in the neutral position and the right crawler 20R is stopped, only the left traveling lever 125L is operated in the forward direction to operate the left crawler 20L in the forward direction. As shown in FIG. 4, the entire self-propelled work machine 10 turns around the front end portion of the right crawler 20R as the turning center O while the caster 74 rolls, and this causes the self-propelled work machine to turn in a narrow space. 10 directions can be changed. Using this small turn, the self-propelled work machine 10 can be turned 180 ° within a narrow landing 29 as shown in FIG.

  In the present invention, the means for operating the extension members 50 and 52 is not limited to the fluid pressure cylinder such as the extension member operation cylinders 66 and 86. For example, when a high driving force is not required, an electric motor or the like can be used. Is possible.

  Next, a second embodiment of the present invention will be described with reference to FIGS.

  In the first embodiment, the front projecting member 50 and the rear projecting member 52 are individually operated by expansion and contraction of dedicated operation cylinders 66 and 86, respectively. In the second embodiment shown, the structure in which the two overhang members 50 and 52 are rotatably connected to the vehicle body frame 18 is the same as that in the first embodiment, but the overhang members 50 and 52 are interlocked. They are interconnected by the mechanism 200 and can be switched alternatively to the following three states by a common interlocking operation cylinder 220.

  a) The front projecting member 50 is in the projecting position as shown by a two-dot chain line 50D in FIG. 12, and the rear projecting member 52 is in its normal storage position (shown by the solid line in FIG. 12) as shown by the two-dot chain line 52U in FIG. A state in which the position is further above (the position shown) (front projecting state).

  b) A state where both the overhanging members 50 and 52 are in the storage position indicated by the solid line in FIG.

  c) The front projecting member 50 is at a position further above its normal storage position as indicated by a two-dot chain line 50U in FIG. 12, and the rear projecting member 52 is projected as indicated by a two-dot chain line 52D in FIG. In the position (rear overhang state).

  Specifically, the interlocking mechanism 200 is constituted by a link mechanism including a pair of left and right intermediate links 202, a front side link 204 arranged at the center in the left and right direction, and a pair of left and right rear links 206.

  Each of the intermediate links 202 is substantially V-shaped when viewed from the side, and the intermediate portion pivots via a pin 210 in the left-right direction to a link bracket 208 that protrudes downward from the left and right rear ends of the body frame 18. Connected as possible.

  The front link 204 connects the front projecting member 50 and the intermediate link 202, and a front link shaft 203 and a rear bifurcated connection member 205 are connected in the front-rear direction. The front end (right end in FIGS. 12 and 14) of the link shaft 203 is connected to the left and right rotation side plates 56 of the front projecting member 50 through the left and right pins 212 (precisely, the two rotation side plates 56 are connected). The left and right rear end portions (left end portions in FIGS. 12 and 14) of the connecting member 205 are connected to the front end portions of the intermediate links 202 (FIGS. 12 and 14). , The right end portion) is connected to each other via a pin 214 in the left-right direction.

  On the other hand, the left and right rear links 206 have a rod shape that connects the intermediate links 202 to the rear projecting member 50, and the front ends (the right ends in FIGS. 12 and 14) of the rear links 206 are left and right. Is connected to the rear end (right end in FIGS. 12 and 14) of the intermediate link 202 via a directional pin 216, while the rear end (left end in FIGS. 12 and 14) of the rear link 206 is The left and right rotation side plates 76 of the rear side overhanging member 52 are connected to the left and right rotation pins 218 via the left and right pins 218 respectively.

  The interlock operation cylinder 220 is provided between the vehicle body frame 18 and the rear extension member 52, and a head side end of the interlock operation cylinder 220 is connected to the rear extension via a pin 222 in the left-right direction. A rod 52 on the rod side of the interlocking operation cylinder 220 is pivotally connected to a caster support plate 78 of the member 52, and a pin in the left-right direction is attached to a cylinder bracket 224 projecting downward from the rear end of the vehicle body frame 18. It is connected via H.226.

  In this structure, when the interlocking operation cylinder 220 is extended most, the rear projecting member 52 is pushed up to a position above the normal storage position (position indicated by a two-dot chain line 52U in FIG. 12). The intermediate link 202 of the interlocking mechanism 20 connected to the side overhanging member 52 rotates in the clockwise direction in FIG. 12, and the front overhanging member 50 is pulled down to the overhanging position indicated by a two-dot chain line 50D in FIG. Overhang). The overhang amount of the front overhang member 50 is smaller than the overhang amount of the front overhang member 50 according to the first embodiment shown in FIG. 4 and the like, but only the overhang amount from the position immediately before reaching the landing shown in FIG. The tilt angle of the lower traveling body 14 to the landing 29 when moving to the landing reaching position shown in FIG. 3 can be reduced, and the impact associated with the falling can be reduced accordingly.

  Further, when the interlocking operation cylinder 220 is stopped at an intermediate position of the stroke, the two overhanging members 50 and 52 are accommodated in the retracted position as indicated by a two-dot chain line 50 in FIG. It becomes possible to travel (stored state). At this time, since both the overhang members 50 and 52 are housed inside the outer shape of the crawlers 20L and 20R when viewed from the side of the vehicle body, the overhang members 50 and 52 are in contact with other obstacles during traveling. Inconvenience is effectively suppressed.

  On the other hand, when the interlocking operation cylinder 220 is most contracted, the rear extension member 52 is lowered to the extension position indicated by a two-dot chain line 52D in FIG. 12, and the interlock mechanism 20 connected to the rear extension member 52 is provided. The intermediate link 202 is rotated counterclockwise in FIG. 12, and the front projecting member 50 is pushed up to a position above the normal storage position (position indicated by a two-dot chain line 50U in FIG. 12) (rear). Side protruding state). In this state, by operating only one of the left and right crawlers 20L and 20R, the self-propelled working machine is accompanied by the rolling of the caster 54 of the rear projecting member 52 around the front end of the other crawler. 10 can be turned in a small turn, and for example, turning at the landing 29 as shown in FIG. 7 is also possible.

  In this embodiment, the interlock operation cylinder 220 does not necessarily have to be connected to the rear projecting member 52, and may be provided, for example, between the front projecting member 50 and the vehicle body frame 18.

  Further, instead of the interlocking operation cylinder 220, the respective states can be switched by rotating the intermediate link 202 with, for example, an electric motor or a hydraulic motor.

It is a side view showing the state where the self-propelled work machine concerning a 1st embodiment of the present invention is climbing up stairs. It is a side view which shows the state in which the said self-propelled working machine exists in the position just before riding on a landing from the said stairs. It is a side view which shows the state after the said self-propelled working machine gets on the said landing. It is a side view which shows the vehicle body frame of the said self-propelled working machine, and the front side extension member and rear side extension member attached to this. It is a top view which shows the said vehicle body frame and an overhang | projection member. (A) is a front view which shows the principal part of the said front side extension member, (b) is a front view which shows the principal part of the said back side extension member. It is a top view which shows the example which the said self-propelled working machine turns in a landing. It is a circuit diagram which shows the state by which hydraulic fluid is supplied to the rod side chamber of an upper work body operation cylinder in the hydraulic circuit mounted in the said self-propelled working machine. It is a circuit diagram which shows the state by which hydraulic fluid is supplied to the head side chamber of a front side extension member operation cylinder in the hydraulic circuit mounted in the said self-propelled working machine. The circuit diagram which shows the state by which hydraulic fluid is supplied to both the rod side chamber of the said upper working body operation cylinder and the head side chamber of the said extension member operation cylinder at the time of synchronous control in the hydraulic circuit mounted in the said self-propelled working machine It is. (A) is a top view of the operation box with which the said self-propelled working machine is equipped, (b) is the front view. It is a side view which shows the vehicle body frame of the self-propelled working machine which concerns on the 2nd Embodiment of this invention, and the front side extension member and rear side extension member attached to this. It is a top view which shows the vehicle body frame and both overhang | projection member of the self-propelled working machine shown by FIG. It is a top view which shows the both overhang members of the self-propelled work machine shown in FIG. 12, and its interlocking mechanism.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Self-propelled working machine 12 Scraper 14 Lower traveling body 16 Upper working body 18 Body frame 20L Left-side crawler 20R Right-side crawler 28 Stairs (slope)
29 landing (upper target)
50 Front projecting member 52 Rear projecting member 66 Front projecting member operation cylinder 74 Caster 86 Rear projecting member operation cylinder 102 Main pump (fluid pressure supply source)
152,154 Front / rear switching valve 200 Interlocking mechanism 202 Intermediate link 204 Front link 206 Rear link 220 Interlocking operation cylinder

Claims (9)

  In a self-propelled working machine having a vehicle body frame provided with crawlers on the left and right and capable of moving up and down the ramp by the operation of the crawler, the crawler is provided in the area of the front half of the crawler and below the lower surface of the crawler It is attached to the vehicle body frame so as to be able to switch between an extended position that extends and supports the vehicle body frame in a front-up state and a retracted position that is stored above the lower surface of the crawler and enables traveling by the crawler. The vehicle body accompanied by rolling of the rolling element by a front projecting member and a rolling element provided in a region in the rear half of the crawler, the rolling element having a rolling element projecting downward from the lower surface of the crawler and landing. A projecting position that enables the frame to turn and a storage position that is stored above the lower surface of the crawler and that allows the crawler to run. A rear extension member attached to the vehicle body frame so as to be switchable, and an extension switching means for moving the front extension member and the rear extension member between the extension position and the storage position, respectively. In addition, the shape and position of the two overhanging members are set so that the front and rear overhanging members in the storage position are within the outer shape of the crawler when viewed from the side of the body frame. A self-propelled working machine.   2. The self-propelled working machine according to claim 1, wherein the projecting position of the rear projecting member is set so that the rolling element is positioned in front of the rear end of the crawler at the projecting position. A self-propelled working machine that is characterized.   3. The self-propelled working machine according to claim 1 or 2, wherein the overhang switching means moves the front overhang member between the overhang position and a retracted position independently of the rear overhang member. And a rear switching means for moving the rear projecting member between the projecting position and the retracted position independently of the front projecting member.   4. The self-propelled working machine according to claim 3, further comprising switching control means for controlling the operation of both switching means so that the front switching means and the rear switching means are operated alternatively. Self-propelled working machine.   5. The self-propelled work machine according to claim 4, wherein each of the front side switching means and the rear side switching means is a fluid pressure actuator that operates by receiving a supply of working fluid, and the switching control means includes the front side switching means and the front side switching means. A fluid pressure supply source provided in common to the rear switching means, a position for guiding the working fluid supplied from the fluid pressure supply source only to the front switching means, and a position for guiding only the rear switching means are selected. A self-propelled working machine comprising a front-rear switching valve that can be switched in a single manner.   The self-propelled working machine according to any one of claims 3 to 5, wherein an extension position of the front extension member is set to a position lower than an extension position of the rear extension member, and the front switching means is It is composed of a front fluid pressure cylinder that expands and contracts by receiving the supply of working fluid, and the rear switching means is a fluid pressure cylinder that expands and contracts by receiving the supply of working fluid and has a smaller expansion / contraction stroke than the front fluid pressure cylinder. Each of the fluid pressure cylinders is connected to the front projecting member and the rear projecting member, and the other ends of the fluid pressure cylinders are both positioned behind the intermediate position in the front-rear direction of the crawler. The self-propelled working machine is connected to the vehicle body frame.   3. The self-propelled working machine according to claim 1 or 2, wherein the overhang switching means includes the front overhang member and the rear overhang member, the front overhang member in the overhang position, and the rear overhang member is the A front extended state in a position above the retracted position; a retracted state in which both the front projecting member and the rear projecting member are in the stored position; and the front projecting member in a position above the retracted position and An interlocking mechanism that interlocks the two projecting members so that the rear projecting member is switched to the rear projecting state at the projecting position, and the interlocking mechanism interlocks the two projecting members so that the front projecting state and the neutral state are A self-propelled working machine comprising interlocking operation means for selectively switching to the rear side overhanging state.   8. The self-propelled working machine according to claim 7, wherein the front projecting member rotates about a left and right support shaft provided at a front portion of the body frame, and the projecting position and the storage position are rotated by the rotation. The rear projecting member is pivoted about a left and right support shaft provided at a rear portion of the vehicle body frame, and the projecting position and the storage are thereby rotated. The intermediate mechanism is attached to the vehicle body frame so as to be rotatable around a left and right support shaft located between the two support shafts. A link, a front link connecting the front end portion of the intermediate link and the front projecting member, and a rear link connecting the rear end portion of the intermediate link and the rear projecting member, Interlock operating means, the front overhang member, the rear overhang member, self-propelled working machine, characterized in that those rotating the one of the intermediate link.   9. The self-propelled working machine according to claim 8, wherein the interlocking operation means is composed of a fluid pressure cylinder that expands and contracts upon receiving a supply of working fluid, and one end of the fluid pressure cylinder has the front side overhang member and the rear side overhang member. A self-propelled working machine characterized in that it is connected to one of the members and the other end is connected to the body frame.

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